Pneumatic Retinopexy

From EyeWiki
Original article contributed by: Amitabh K. Bharadwaj, MD
All contributors: Amitabh K. Bharadwaj, MD, Jennifer I Lim MD and Vinay A. Shah M.D.
Assigned editor: Felix Y. Chau, MD
Review: Assigned status Update Pending by Vinay A. Shah M.D. on December 21, 2014.


Introduction

Pneumatic retinopexy was introduced by Hilton and Grizzard in 1986 as an outpatient procedure to repair rhegmatogenous retinal detachments.[1] It supplemented the preexisting operative procedures used to repair rhegmatogenous detachments including scleral buckling and pars plana vitrectomy. It is an effective, non-invasive method of retinal detachment repair in selected cases.[2] [3]

Indications

  • Retinal break(s) within the superior 8 clock hours (8 to 4 o’clock)
  • Single or multiple breaks within 1 clock hour
  • No or minimal media opacity
  • Patient able to maintain positioning for 5-8 days after procedure

Expanded Indications

  • Pseudophakia or aphakia
  • Up to grade A or B PVR
  • Retinal breaks up to 3 clock hours apart
  • Up to 3 clock hours of lattice degeneration[4]

Contraindications

  • Breaks within the inferior 4 clock hours
  • Grade C or D PVR
  • Extensive lattice degeneration or traction
  • Significant media opacity
  • Severe glaucoma
  • Patient unable to maintain postoperative positioning
  • Patient must fly or travel to altitude soon after surgery

Advantages

  • Outpatient procedure
  • Less discomfort than operating room procedures
  • No need for MAC or general anesthesia
  • No change in refractive error
  • No diplopia
  • Less risk of infection
  • Faster ocular and systemic recovery
  • Lower cost procedure
  • Patient can still have operating room procedure without affecting prognosis

Disadvantages

Single-operation success rate is lower than operating room procedures.  One survey of the literature revealed a cumulative initial success rate of 75.5%, with a final success rate of 97.4%, as opposed to the initial success rates of pars plana vitrectomy and scleral buckling which are in the 85-88% range.[5]  Failure of pneumatic retinopexy is thought to be due to reopening of one of the original breaks, or to missed or new tears.  Studies have generally reported higher success rates for pneumatic retinopexy in phakic eyes, likely due to missed or new tears in pseudophakes and aphakes. 

  • Requires a surgeon highly skilled at retinal examination
  • Not all detachments are amenable to repair with pneumatic retinopexy
  • Requires significant patient cooperation and positioning
  • Surgeon must be able to manage postoperative care and complications

Surgical Procedure

Instrumentation

  • 2% Lidocaine
  • 10% Betadine
  • Laser or Cryotherapy unit
  • Intraocular gas (SF6 or C3F8)
  • Millipore filter
  • Indirect ophthalmoscope

Operation

  1. Retinal reexamination with confirmation of all areas of pathology.
  2. Local anesthesia administered for patient comfort. Use 2% lidocaine subconjunctivally or give a retrobulbar block if needed.
  3. Cryotherapy is applied to pathology in detached retina. Highly elevated breaks may be flattened by a steamroller maneuver. Care should be taken to avoid excess cryotherapy to prevent possible release of RPE cells and subsequent PVR formation.[6] Laser photocoagulation can be used in attached areas of retina. Pseudophakic and high risk eyes may benefit from 360-degree laser.
  4. Prepare intraocular gas. Use either SF6 or C3F8 drawn into a tuberculin syringe through the filter to provide tamponade of the detachment. Use the smallest bubble needed to cover the pathology, keeping in mind that the gas volume needed to cover a given arc of retina will increase with myopia. Pre-fill the system to remove dead space before drawing up the amount of gas to be injected and attaching a 30-gauge needle. SF6 will expand 2x and lasts for 1-2 weeks, wheras C3F8 will expand 4x and lasts 4-8 weeks.
  5. Set up a sterile stand or towel near the eye for placing instruments. 10% Betadine drops are placed onto the eye. Some surgeons prefer to do a modified lid scrub. In patients with an allergy to Betadine, a broad-spectrum topical antibiotic may be used.
  6. An anterior chamber paracentesis can be performed safely at this stage, and is especially useful in patients with glaucoma. The eye is stabilized with a cotton-tip swab, and a 27-gauge needle attached to a tuberculin syringe is used to enter the anterior chamber at the limbus. 0.2 - 0.4cc of fluid is usually withdrawn from the anterior chamber.
  7. Intraocular gas injection. This is done through an entry site in a quadrant away from the detachment. Enter the eye vertically 3.5 - 4mm from the limbus, depending on the lens status, and inject the gas at a moderate pace. Injection of gas too quickly can cause a “fish eggs” phenomenon, which may require gentle tapping on the eye or positioning the bubbles away from the break for 24 hours to allow them to coalesce and avoid subretinal gas. To minimize the chance of fish eggs, it is helpful to pull the needle back a millimeter after the injection has begun to maintain one large gas bubble. Another potential complication is gas injection into the Canal of Petit, in which case it can be seen floating behind the lens as a “donut sign” or “sausage sign”; management may include overnight face-down positioning, which is usually effective, or passive drainage with a 27-gauge needle on a tuberculin syringe partially filled with BSS.  Lastly, gas in the anterior chamber likely represents anterior migration due to ruptured zonules and can be managed by pupillary dilation followed by face-down positioning or by AC paracentesis with a 27-gauge needle.
  8. Evaluation of IOP. Carefully evaluate the central retinal artery and confirm light perception. Loss of pulsations lasting longer than a few minutes requires decompression through an anterior chamber paracentesis.
  9. Antibiotic or combination antibiotic/steroid ointment is applied to the eye and it is patched.

Postoperative Care

  • Positioning for 5-8 days to orient gas bubble at the site of the tear(s).  The patient must position for 16 hours per day, with 15-minute breaks each hour.
  • Antibiotic eyedrops four times per day, usually for 1 week
  • Follow up the next day and continue to observe for resolution of detachment.  
  • Appropriate management of postoperative complications and additional surgery as indicated

Additional Resources

References

  1. Hilton GF, Grizzard WS. Pneumatic retinopexy (a two-step outpatient operation without conjunctival incision). Ophthalmology. 1986;93:626–641.
  2. Brinton DA, Hilton GF. Pneumatic retinopexy and alternative retinal detachment techniques, in Ryan SJ, Wilkinson CP (eds). Retina. 2001, pp.2047-62.
  3. Tornambe PE, Hilton GF, Kelly NF, et al. Expanded indications for pneumatic retinopexy. Ophthalmology. 1988; 95:597-600.
  4. Tornambe PE. Pneumatic retinopexy: The evolution of case selection and surgical technique, a twelve-year study of 302 eyes. Trans Am Ophth Soc 1997;95:551-78.
  5. Holz ER, Mieler WF.  View 3:  The case for pneumatic retinopexy.  Br J Ophthalmol.  2003;87:787-89.
  6. Campochiaro PA, Kaden IH, Vidaurri-Leal J, Glaser BM. Cryotherapy enhances intravitreal dispersion of viable retinal pigment epithelial cells. Arch Ophthalmol. 1985;103:434.